1. Field of the Invention
The present invention relates to an image forming system that allows data transfer from an image forming apparatus to another image forming apparatus by user's instruction or for backup or an image forming system that allows data transfer as the data are attached to an e-mail from an image forming apparatus to a device, and an image forming apparatus, a device, and a data erase program for use in the system.
2. Description of the Related Art
The following description sets forth the inventor's knowledge of related art and problems therein and should not be construed as an admission of knowledge in the prior art.
As generally known, in conventional common network-connected image forming apparatuses, image data such as facsimile (hereinafter, referred to as FAX) data, print data, and scan data are used repeatedly as the data are stored in a hard disk drive (hereinafter, referred to also as HDD) therein.
In regard to the HDD, a typical memory device in such an image forming apparatus, there is a concern about partial or entire destruction of the stored data due to breakdown of HDD itself or other reasons, because of its mechanical structure. Thus, Japanese Unexamined Patent Publication No. 2004-230617 proposes a method of improving the security of data stored in an image forming apparatus by backuping periodically the data in a HDD of a printer connected to the same network, and thus this method enables the stored data recoverable just in case.
On the other hand, to prevent insufficient memory causes slowdowns of printer processing, that results from the large increase of stored data due to various functions added to printers, Japanese Unexamined Patent Publication No. 2000-330752 proposes a method of transferring the data into another printer temporarily for efficient use of the memory in the image forming apparatus.
However, the conventional methods described above may cause a problem that, even when a user intends to erase data stored in an image forming apparatus and inputs an erase instruction on the image forming apparatus, the transferred data at the transfer destination practically remains unerased, contrarily to user's original intension. In particular when the data to be erased is, for example, a confidential document, there will be a problem of insufficient security. Such a problem arises similarly even when the data is transferred to another image forming apparatus or sent to another device as e-mail-attached data according to user's instruction, or in an image forming system when the data is periodically backupped, for example at night, into another image forming apparatus.
The description herein of advantages and disadvantages of various features, embodiments, methods, and apparatus disclosed in other publications is in no way intended to limit the present invention. Indeed, certain features of the invention may be capable of overcoming certain disadvantages, while still retaining some or all of the features, embodiments, methods, and apparatus disclosed therein.